Jeep Engines - Oljeep

382 MOPAR PERFORMANCE PARTSThe compressed Plastigauge should maintain the same sizeacross the entire width of the insert. If the size varies, thismay indicate either a tapered journal or foreign materialtrapped behind the insert.If the correct clearance is indicated, bearing replacement isnot necessary. Remove the Plastigauge from the crankshaftand insert. Proceed to crankshaft Installation. Small piecesof Plastigauge may remain on the insert or journal surfaces.It will dissolve in the hot engine oil when the engine isoperated.If the oil clearance exceeds the specification, install a pairof 0.025 mm (0.001") undersize bearing inserts andmeasure the clearance as described earlier.The clearance measured with 0.025 mm (0.001") undersizeinserts installed will determine if a pair of 0.025 mm(0.001") undersize inserts or some other size combinationwill provide the correct clearance.Example: If the clearance was 0.089 mm (0.0035")originally, a pair of 0.025 mm (0.00ll') undersize insertswill reduce the clearance by 0.025 mm (0.001"). The oilclearance will be 0.064 mm (0.0025") and within thespecification. The combination of a 0.051 mm (0.002")undersize insert and 0.025 mm (0.001") undersize insertwill reduce this clearance by an additional 0.013 mm(0.0005") and the oil clearance will be 0.05 1 mm (0.0021').Caution: Never use a combination of inserts that have adifference of more than one bearing size. For example, DONOT use a standard upper and 0.051 mm (0.002")undersize lower insert.If the oil clearance exceeds the specification with a pair of0.051 mm (0.002") undersize inserts, measure thecrankshaft journal diameter with a micrometer. If thejournal diameter is correct, the crankshaft bore in thecylinder block may be misaligned, which requires cylinderblock replacement. If the journal diameter is incorrect,replace or grind the crankshaft to the standard undersize.Main Bearing Journal Diameter - CrankshaftRemovedWipe the main bearing journals clean.Measure each journal diameter with a micrometer. Note thedifference between the maximum and minimum diametersof each journal. (Refer to 360 AMC V-8 EngineSpecifications, 'Engine Assembly' section of this chapter,for the maximum allowable taper and out-of-roundness.)Compare the largest journal diameter you measured withthe journal diameter listed in the Main Bearing FittingChart (Figure 7-3).Select the insert pairs that will provide the specifiedbearing clearance. Refer to 360 AMC V-8 EngineSpecifications, 'Engine Assembly' section of this chapter,for the correct clearance.Installation1. Lubricate the journal contact surface of each insertwith clean engine oil.2. Loosen all main bearing caps.3. Install the main bearing upper insert(s).4. Install the main bearing cap(s) and lower insert(s).Tighten the retaining bolts evenly to 136 Nom (100 ftlbs)torque in steps of 41,81,122 and 136 N*m (30,60,90 and 100 ft-lbs) torque. Rotate the crankshaft aftereach tightening step to determine if it rotates freely. Ifit does not rotate freely, examine the inserts for properinstallation and size.5. Install the oil pan using replacement gaskets and seals.Tighten the drain plug securely.6. Fill the crankcase to the specified level with cleanengine oil.Crankshaft End PlayCrankshaft end play is controlled by the No. 3 mainbearing, which is flanged for this purpose.1. Attach a dial indicator to the crankcase adjacent to theNo. 3 main bearing.2. Set the dial indicator stem on the face of the adjacentcounterweight (Figure 7-4).3. Pry the crankshaft fore and aft (Figure 7-4).4. Note the dial indicator readings. End play is thedifference between the high and low measurements.The proper crankshaft end play is 0.08-0.20 mm(0.003-0.0081).5. If the end play is not within the specification, inspectthe crankshaft thrust faces for wear. If no wear isapparent, replace the No. 3 (thrust) main bearinginserts and measure the end play. If the end play is notwithin specification, replace the crankshaft.Note: When installing the No. 3 (thrust) main bearinginserts, pry the crankshaft fore and aft to align the thrustfaces of the bearing inserts before final tightening.